Refrigerating apparatus



March 14, 1939. H. B. HULL REFRIGERATING APPARATUS Filed July 51, 1953-3 Sheets-Sheet l INV g 3 m 2 8 8 2 2 S 8 S S 2 8 g 1 8 2 is 8 J 8 u5.... 2 a

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March 14, 1939. H. B. HULL REFRIGERATING APPARATUS Filed July 31, 1933 3Sheets-Sheet 2 llll "A" ATTORNEYW Patented Mar. 14, 1939 UNITED STATES2,150.22; 7, nnraresm'rmo mmzrus Harry B. Hull, Dayton, Ohio, assignorto General Motors Corporation, Dayton, Ohio, a corporation of DelawareApplication July 31, 1933, Serial No. 682,9" 7

x X 20 Claims.

ratus and more particularly to apparatus .for

cooling air, as, for instance, in rooms or the like.

One of the objects of the present invention is to provide an improvedapparatus for cooling and circulating air in rooms or the like.

Another object'of this invention is to provide an improved apparatuswhich automatically circulates the air in the room, reduces the humidityand maintains said air at. a predetermined temperature.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings, wherein apreferred form of the present invention is clearlyshown.

In the drawings:

Fig. 1 is a vertical cross sectional view, semidiagrammatic incharacter, of a room cooler or air conditioner embodying my invention;

Fig. 2 is a view somewhat similar to Fig. 1; but disclosing a difierentarrangement of air conditioning coils and casing;

Fig. 3 is a view similar to Fig. 2, but showing automatic controlsapplied thereo;

Fig. 4' is' a view of a unitary portable air conditioner embodyingfeatures disclosed both in Figs. 1 and 2 as'well as further features; f

Fig. 5 is a view in elevation of an apparatus for controlling theoperation of the air conditioners herein disclosed in accordance withthe temperature of the air; v

Fig. 6 is a cross sectional view of the water valve shown in Fig, 3; n

Fig. '7 is a diagrammatic representation of the application of thedevice shown in Fig. 5 to the various air conditioner. and

Fig. 8 is a diagrammatic representation of a modified portion of Fig. 7.

In the particular embodiment shown in Fig. 1 air is circulated through acabinet I by means of an electrically operated fan or means I62 whichdraws the air through louvers I64, through an air treating zone I66 anddischarges the treated air through a screened opening I68 provided inthe top of the cabinet I60. A plurality of cooling coils I10 connectedin series by means of pipes are adapted to cool the air to a temperaturebelow its dew point so that when the air is rewarmed it will be at thedesired relative humidity, which rewarming may be accomplished by aplurality of coils I15 disposed above the from striking occupants of thecooled condenser I95 through pipe I 96.

coils I10 thus preventing cold saturated air room. Refrigerant iscirculated in a closed path through the coils I10 by means of arefrigerant circulating element I under the control of an expansionvalve I 8|. The element I80 delivers the liquid refrigerant through pipeI and withdraws the gaseous refrigerant through pipe I81. The elementI80 comprises a compressor I operatively connected with a motor I9I bybelt I92. The motor I9I is controlled by a switch I93 actuated by athermostat I94 in response to the temperature of pipe I81. Thecompressor I90 compresses the gaseous refrigerant and delivers it to awai -fir e gaseous refrigerant is liquefied in the condenser I95 andfrom which it is delivered through pipe I85 to the coils I10. Theheating coils I15 are heated by water passing through cofl 200 used forliquefying the refrigerant in the condenser I95. The coil 200 used forliquefying the refrigerant is provided with an inlet 20L The water thenpasses through pipe 208, heating coils I15 to an outlet pipe 2| 0. Thewater inlet' 20| may be connected to any suitable water pressure systemwhile the outlet pipe 2I0 may be connected to the waste system. In theapparatus shown in Fig. 1, the electricallyoperated fan I62 draws theair through the louvers I64 and. some air through cutaway portions ofthe cabinet I60 as shown at 2I I. The air is then forced through anoperiing 2I5 provided in a drip or moisture pan 2| 6 whence the air isforced along the loops of coils I10 and coils I15 and is then dischargedthrough the screened opening I68. A bonnet or hood 2l9 is provided toprevent moisture from the coils from dripping through the opening 2I5. Athermostatic switch of the type shown in Fig. 5- may be employed forcontrolling the operation of the electrically operated fan I62 and theflow of current to the contacts of the switch I93 as diagrammaticallyshown in Fig. '7. Thus it will be noted that refrigerant is circulatedthrough the air treated zone for cooling the air to a temperature belowits dew point and'that the air is later rewarmed so that the dischargedair will have the desired relative humidity and that in rewarming saidair a part of the heat, of

treating zone 226. The air is circulated through the treating zone bymeans of an electrically driven fan or means 238 and is later dischargedthrough duct 23! provided with sound insulating material 232, which ductleads to a screened opening 233 through which the air is discharged intothe room being cooled. In the present instance I have provided a waterflow apparatus comprising a plurality of longitudinally disposed coils240 ,connected in series by means of pipes 24! and 242.

The water flow apparatus is arranged for precooling the air entering theair treating zone 225. The water flow apparatus is provided with aninlet pipe 243 and outlet pipe 244. The air circulating through thetreating zone is precooled by the water flow apparatus and is latercooled to the desired temperature by means of a refrigerant circulatingapparatus comprising a plurality of longitudinally disposed coolingcoils 250 located above the water flow apparatus in the air treatingzone 226. Refrigerant is circulated through the coils 250 by means of arefrigerant circulating element 255 under the control of an expansionvalve 256. The element 255 delivers refrigerant through a pipe 258 andwithdraws the gaseous refrigerant through a pipe 260. The element 255comprises a compressor 26! operatively connected with a motor 262 bymeans of belt 263. The motor 262 is controlled by a switch 265 actuatedby a thermostat 261 in response to the temperature of pipe 269. Thecompressor 26l compresses the gaseous refrigerant and delivers it to anair cooled condenser 269 wherein it is liquefied and from which it isdelivered to a receiver 21 to which the pipe 258 is connected. Ifdesired, automatic means for controlling the operation of the electrically operated fan 230 and for controlling the flow of current tocontacts of switch 265 of the type shown diagrammatically in Fig. 5 maybe employed for controlling the operation of the apparatus shown in Fig.2 in a manner somewhat similar to that indicated in Fig. 7.

. In Fig. 3 there is shown a modified form of room cooling apparatus,adapted to be placed in a room or enclosure, comprising a cabinet orcooler chamber 215 forming an air treating zone 216. The cabinet is cutaway as at 211 which permits air to enter the air treating zone at thelowermost portion thereof whence the air is later discharged through ascreened opening 288. The air is circulated through the treating zone bymeans of an electrically driven fan or means 28 I In the particularapparatus I provide a water flow apparatus comprising a plurality ofcooling coils 283 extending across the cooler chamber controlled by anelectrically operated valve 284 through which a cooling medium fiows,such as water. I also provide a refrigerant circulating apparatusincluding a plurality of coils 281 located above the water flowapparatus through which a cooling medium flows, such as a volatilerefrigerant. Refrigerant is delivered to the coils 281 by means of arefrigerant circulating element 298 under the control of an expansionvalve 29 I The element 290 delivers the liquid refrigerant through apipe 293 and withdraws gaseous refrigerant through a pipe 294. Theelement 290 comprises a compressor 295 operatively connected with amotor 296 by belt 291. The motor 296 is controlled by a switch 300actuated by a thermostat 30I in response to the temperature of pipe 296.The compressor 295 compresses the gaseous refrigerant and delivers it toan air cooled condenser 302 wherein it is liquefied and from which it isdelivered to a receiver 384 which is connected to the pipe 293. Thewater flow coils 283 are provided with an inlet connection 306 andoutlet connection 301.

In order to provide means for controlling the operation of theelectrically driven fan 28l and the electrically operated valve 284 andfor controlling the flow of current to contacts 3l0 of switch 300 athermostatic switch 3 l2 has been provided. As shown in Fig. 5 thethermostatic switch 3|2 is provided with a bimetallic thermostaticcoiled blade 3|4 and a plurality of mercury containing tubes or bulbs3I5 and 316. The switch 3l2 is adapted to control the valve 284 and thefan at a predetermined room temperature which may be determined by theposition of the adjustable handle or indicator 320 of switch 3I2. Asshown in Fig. 6 the electrically operated valve includes a magnetwinding 322 and a movable core 323 which carries the valve proper 325.The valve 284 is provided with an inlet passage 321 in a casing 328 andan outlet passage 329. When the magnet winding 322 becomes energized,the core 323 will be moved upwardly to move the valve proper 325 fromthe seat to thus allow unrestricted communication between the inletpassage 321 and the outlet passage 329 to thus permit the circulation ofWater through the coils 283. The switch 3|2 is adapted to place themagnet winding 322 of valve 284 andthe motor 330 which operates the fan28! in circuit with the power mains 332 and 333 when the temperature ofthe room attains a predetermined value, for instance, the temperature asindicated by the indicator 328. Thus when the temperature of the roomreaches the point indicated by the indicator 328, the switch 3| 2 willallow the current to be supplied to the magnet winding 322 of valve 284and to the motor 336 to cause water to circulate in coils 283 and tocause air to circulate through the air treating zone 216 by theoperation of fan 28!. The circuit through the magnet winding 322 ofvalve 284 and through the motor 330 is as follows: Power main 333, wire340, magnet winding 322, wire 34l, motor 330, wire 342, contacts ofmercury containing tube 315 which contacts are completed by theengagement of the mercury drop 345 therewith, and wire 341 which isconnected to power main 332. If the temperature of the room continues toincrease, for instance, to an increase of five degrees over the desiredtemperature as indicated by indicator 320, the bimetallic thermostaticblade 3l4 will cause the rotation of the mercurycontaining tube 3 l 6 tothus cause the mercury drop 358' to engage the contacts of the mercurycontaining tube 3l6 to complete a circuit through the contacts 3| 0 ofswitch 360 to thus allow current to flow from the power mains to themotor 296 to thereby actuate the compressor 295. The circuit through themotor 296 is power main 333, wire 352, motor 296, contacts 3"] of switch308, wire 355, wire 354, contacts of mercury containing tube 3|6 andwire 356 which is connected with power main 332. From the foregoing itwill be noted that when the temperature of the room attains apredetermined amount above the setting of the indicator 320 of switch3|2, the electrically operated fan 2! and the electrically operatedvalve 284 will be actuated to thus cause the flow of water in the coils283 and the circulation of air through the air treating zone 216.However, should the water fiow apparatus and the fan 28l be unable tomaintain the desired temperature in the room to be cooled therefrigerating element 290 would be rendered operative to supplyrefrigerant to the coils 281 to thus reduce the temperature in the roomto the temperature indicated by the indicator 320 of switch 3|2.

I it is delivered to pipe 428 to a water cooled con- When thetemperature of the room is reduced to a temperature below that indicatedby the means 328, the thermostat 314 will cause the rotation of mercurycontaining tube 316 to separate the mercury drop 358 from the contactsof the tube 316 to thus interrupt the flow of current to the motor 286to thereby render the refrigerant circulating element inoperative. Inthe event the temperature of the room should fall below the desiredtemperature, as indicated by means 328 of switch 3l2, by the operationof the water flow apparatus and fan alone, the thermostat 3l4 willactuate the mercury containing tube M to thus separate the mercury drop345 from the contacts of mercury tube M5 to thus interrupt the circuitto the motor 338 and to the magnet winding 322 of valve 284 to thusclose the valve to thus prevent the circulation of water in' the coils283 and render the fan 28l inoperative. By this construction the coolingmedium supplied to the banks of coils 283 and 281, extending across thecooler chamber 215, is independently and automatically varied so thatthe cooling effect of each bank on the air is varied in accordance withrefrigeration demands.

If desired, the water inlet pipe 386 may be provided with a manuallyoperable valve 580 as shown in Figure '7, so that the fan 28| may becaused to operate to create an air current in the room without anycooling whatsoever merely by closing the manually operable valve 588 andby operating the manual switch 58| placed acrosst he leads to theautomatic control 3| 2. Under such conditions,-

the pointer 328 should be adjusted to a temperature higher than anytemperature likely to be reached by the air in the room. When under suchsetting and condition, the motor 338'will operate continuously and waterwill be prevented from' flowing through the coil 283 by the valve 588,and

no refrigerant will flow through the coil 281, because the control 3l2is adjusted above the normal range of the air in the room.

Referring to Fig. 4 there is shown a modified form of room coolingapparatus which comprises a cabinet 315 forming an air treating-zone orupper air cooling and dehumidifying section 318 and is provided with amachinery compartment or lower refrigerant circulating section 319. The

cabinet is provided with louvers 388 through which the air enters theairtreating zone 318. The air is. forced through an opening 382 in amoisture pan 383 by means of an electrically operated fan 385. The airis then forced through a water cooling apparatus comprising coils 388which pre-cool the'air. The air, when artificial cooling is desired, isthen cooled to a temperature below its dew point by refrigerant coolingcoils 398 so that when the air is rewarmed it will have the desiredrelative humidity, which rewarming may be accomplished by utilizing partof the heat of liquefaction which is liberated from the coil 392 toprevent cold saturated air from striking occupants or the room. When theair is treated to the desired temperature said air is discharged througha screened opening 385 provided in-the top of the.

and delivers it to the air cooled condenser or coil 392 where it ispartially liquefied and from whence pressor 4l8 compresses the gaseousrefrigerant denser 422 are provided with a common inlet 425 and commonoutlet connection 426. v Thus water will enter inlet 425 and circulatethrough the coils 388, condenser coil 428 which is connected to a watercoil 438 by pipe 43! which water coil 438 is adapted to remove the heatfrom the machinery compartment 319.

Fig. '1 is a diagrammatic representation to indicate how the controlsshown in Figs. 5 and 6 are applied specifically to the apparatus shownin Fig. 3; but it is to be understood that the same controls can beapplied to all of the modifications shown in Figs. 1, 2, 3 and 4inclusive. Similar reference characters have been used in Figs. 7 and 3,so that the various parts in the two figures can be readily identifiedwithout further description.

In Fig. 8, a modification of a portion of Fig. 7

is shown in which the motor 286a, driving the any appreciable quantityfrom flowing past the thermostatic bulb 582. The switch 388a is operatedin response to pressure in the refrigerant suction line 294a. byconnecting the pipe 583 with the suction line 294a and the bellows 584of the switch 388a. This modification or arrangement will be readilyunderstood by those skilled in the art, and the remainder of thestructure illustrated in Fig. 7 is understood to be incorporated orcombined with the structure shown in Fig. 8, the only change thusaccomplished being that the compressor motor in Fig. 8 is controlled inaccordance with refrigerant pressure in the evaporator, whereas in Fig.'7 the compressor motor is controlled in accordance with the temperatureat the outlet end of the evaporator.

In all of the modifications, the controls are preferably set so that theevaporators do not attain a temperature below the freezing point ofwater, thus preventing. the accumulation of frost on the evaporators.

While the form of embodimentof the present invention as hereindisclosed, constitutes a preferred form, it is to be understood thatother forms might be adopted all coming within the scope of the claimswhich follow.

What is claimed is as follows:

1. The method of refrigeration which comprises circulating refrigerantin a closed path, condensing said refrigerant in one zone of said pathand evaporating said refrigerant in a second zone, circulatingair' toand from a main body along said second zone to thereby cool the air,circulating water in a closed path through said second zonev forremoving heat from the air passing through said second zone, andautomatically controlling the circulation of the refrigerant, the airand the water in accordance with the temperature of the air.

2. The method of refrigeration which comprises circulating refrigerantin a closed path, condensing said refrigerant in one zone of said pathand evaporating. said refrigerant in a second zone, circulating air toand from a main body along said second zone to thereby cool the air,circulating water in a closed path throughsaid second zone for removingheat from the air passing through said second zone, and automaticallycontrolling the circulation of refrigerant in response to predeterminedenvironment temperature, and automatically controlling the circulationof the air and the water at a diflerent predetermined environmenttemperature.

3. An apparatus for conditioning air including means forming an airtreating zone, a refrigerant circulating apparatus having an evaporatorin said zone, electrically operated means for forcing air through saidzone, a switch adapted to actuate a set of contacts for controlling theoperation of said circulating apparatus, means responsive to thepressure in said evaporator for con trolling said switch, and meansresponsive to the temperature 'of the air for controlling saidelectrically operated means and for controlling the flow of current tosaid switch.

4. An apparatus for conditioning air including means forming an airtreating zone, a refrigerant .circulating apparatus having an evaporatorin said zone, a water flow apparatus having connections for removingheat from the air passing through said zone,valve means for controllingsaid water flow apparatus, means for circulating air through said zone,and means responsive to the temperature of the air for simultaneouslycontrolling said air forcing means and said valve means.

5. An apparatus forconditioning air including means forming an airtreating zone, a refrigerant circulating apparatus having an evaporatorin said zone, a water flow apparatus having connections for removingheat from the air passing through said zone, valve means for controllingsaid water flow apparatus, means for circulating air through said zone,means responsive to the environment temperature for simultaneouslycontrolling said air forcing means and said valve means, saidtemperature responsive means also controlling said refrigerantcirculating apparatus.

6. An apparatus for conditioning air including means forming an airtreating zone, a refrigerant circulating apparatus having an evaporatorin said zone, a water flow apparatus having connections for removingheat from the air passing through said zone, valve means for controllingsaid water flow apparatus, means for circulating air through said zone,means including a mercury containing bulb for controlling said airforcing means and said valve means, a second mercury containing bulb forcontrolling said refrigerant circulating apparatus and a singletemperature responsive device for controlling said bulbs.

'7. A unitary portable apparatus for conditioning air comprising acabinet forming an air treating zone, a liquid refrigerant evaporator insaid zone, a water flow coil in said zone below said evaporator, saidwater flow coil having connections for removing heat from the airpassing through said zone, means for forcing air through said zone, andmeans located over said evaporator for partially condensing therefrigerant by air cooled in said zone.

8. A unitary portable apparatus for conditioning air comprising acabinet forming an air treating zone, a refrigerant circulatingapparatus said apparatus having an evaporator in said zone, a water flowapparatus having connections for removing heat from the air passingthrough said zone, said water flow apparatus being located in said zonebelow said evaporator, means for forcing air through said zone, saidrefrigerant circulating apparatus having means in said zone above saidevaporator for partially condensing the refrigerant by air cooled insaid zone, and a water cooled condenser in said zone.

9. An apparatus for conditioning air comprising a unitary casing, a fanand an evaporator in said casing, an air inlet and an air outletarranged to permit air to be conditioned to flow through said inlet,outlet, fan and evaporator, a refrigerant liquefying unit connected inrefrigerant flow relationship with said evaporator at least a portion ofwhich refrigerant liquefylng unit is enclosed in a machinery compartmenthaving an air space, and a-water coil in the air space 01' saidmachinery compartment separate from said liquefying unit.

10. An apparatus for conditioning air comprising a unitary casing, a fanand an evaporator in said casing, an air inlet and an air outletarranged to permit air to be conditioned to flow through said inlet,outlet, fan and evaporator, a refrigerant liquefyingunit connected inrefrigerant flow relationship with said evaporator and including amotor, compressor and condenser, said motor and condenser being placedin a machinery compartment having an air space, and a water coil in theair space of said machinery compartment separate from said liquefyingunit.

11. An apparatus for conditioning air comprising a unitary casing, a fanand an evaporator in said casing, an air inlet and an air outletarranged to permit air to be conditioned to flow through said inlet,outlet, fan and evaporator, a refrigerant liquefying unit connected inrefrigerant flow relationship with said evaporator and including amotor, compressor and condenser, said motor and condenser being placedin a ma chinery compartment having an air space, a water coil in the airspace of said machinery compartment separate from said liquefying unit,and water flow connections causing the flow of cooling water throughsaid condenser and water coil,

12. In an air conditioning apparatus, in combination with an enclosurein which conditioned air is used, a cooler chamber, a fan for passingair to be supplied to the enclosure through said chamber, a plurality ofcooled surfaces extending in the path of the air flowing through saidchamher, means for supplying cooling medium inside stream through saidchamber, a plurality of cooled surfaces across the cross section of saidcooler in the path of said air stream, means for supplying coolingmedium inside said surfaces,

.means for-modifying the supply of cooling medium to one of saidsurfaces in accordance with a psychrometrlc function of air and meansfor modifying the supply of cooling medium to another of said surfaoesinaccordance with a psychrometric function of air.

14.-An air conditioning apparatus, inv combination with anfienclosure inwhich conditioned air is used, air-flow means for air to be conditionedfor said enclosure, a water-flow coil in said means cooling air passingthrough said means, an evaporator ,in

said means cooling air passing through q tor in said upper section;

said means, a refrigerant condensing unit connected to said evaporator,and a common source of water supply connected to said water-flow coiland to said condensing unit.

15. An air conditioning apparatuain' combination with an enclosure inwhich conditioned air is used, air-flow means for air to be conditionedfor said enclosure, a water-flow coil in said means cooling air passingthrough said means, an evaporator in said means cooling air passingthrough saidmeans, and means controlling the flow of water through saidwater-flow coil in accordance with a temperature condition, and meansconwhereby a current of cooled air is forced through said duct.

17. A unitary room cooler and dehumidifier to be used in a room or thelike where refrigeration is desired to maintain the temperature andhumidity of the air in said room or the like within the values boundingthe human comfort range, comprising a cabinetwith upright substantiallyvertical walls with an upper air cooling and dehumidifying section and alower'refrigerant circulating section; a refrigerant evaporator in saidupper section; a refrigerant compressor, an electric compressor motordrivingly connected to said compressor anda refrigerant condenser insaid lower section; said evaporator, compressor and condenser beingconnected in refrigerant flow relationship; air intake forming means insaid cabinet located a substantial distance above the floor of said roomto introduce air from said room into the lower part of said uppersection; air discharge forming means in the upper part of said uppersection; an air circulato'r and an electric air circulator motordrivingly connected to said air circulator causing the flow of air fromsaid room into said air intake forming means, past said evaporator, andout of said air discharge forming means; control means including aswitch for causing operation of said air circulator motor whenever saidcompressor motor operates, and a device responsive to a psychrometricfunction of air conditions in said room controlling theoperation of saidcompressor; said air circulator, evaporator, compressor and condenserbeing correlated with each other to maintain said evaporator temperatureabove freezing and below the minimum dew point temperature prevailing ata time when artificial air cooling is desired, whereby the accumulationof frost on said evaporator is prevented and moisture may be condensedfrom tHe air passing over said evaporator.,

18. A unitary room cooler and dehumidifier to be used in a room or thelike where refrigeration is desired to maintain the temperature andhumidity of the air in said room or the like thehuman comfort within thevalues bounding with upright subrange, comprising a cabinet stantiallyyertical walls with an upperair cooling and a lower refrig" anddehumidifying section erant circulating section; a refrigerantevaporaupper section located a refrigerant com-- air toprecool the airbeforeit flows past said pressor, an electric compressor motor drivinglyconnected to said compressor and a refrigerant condenser in said lowersection; said evaporator, compressor and condenser being connected inrefrigerant flow relationship; air intake forming means in said cabinetlocated a substantial distance ,above the floor of said room tointroduce air from said room into the-lower part of said upper section;air discharge forming means in the upper part of said upper section; anair circulator and an electric air circulator motor drivingly connectedto said air circulator causing the flow of air from said room into saidair intake forming means, past said evaporator, and

out of said air discharge forming means; control means including aswitch for causing operation of said air circulator motor whenever saidcompressor motor operates, and a device responsive to a psychrometricfunction of air conditions in said room controlling the operation ofsaid compressor; said air circulator, evaporator, compressor andcondenser being correlated with each other to maintain said evaporatortemperature above freezing and below the minimum dew point temperatureprevailing at a time when artificial air cooling is desired, whereby theaccumulation of frost on said evaporator is prevented and moisture maybe condensed from the air passing over said evaporator; and a watercirculating, air cooling apparatus in said upper section located in thepath of said flow of air to precool the air before it flows past saidevaporator. 19. A unitary room cooler and dehumidifier to be used in aroom or the like where refrigeration is desired to maintain thetemperature and humidity of the air in said room or the like within thevalues bounding the human comfort range, comprising a cabinet withupright substantially vertical walls with an upper air cooling and de-.humidifying section and a lower refrigerant circulating section; arefrigerant evaporator in said upper section; a refrigerant compressor,an electric compressor motor drivingly connected to said compressor anda refrigerant condenser in said .lower section; said evaporator,compressor and condenser being connected in refrigerant flowrelationship cabinet located a substantial distance above the floor ofsaid room to introduce air from said room into the lower part of saidupper section; air discharge forming means in the upper part of saidupper section; an air circulator and an electric air circulator motordrivingly connected to said air circulator causing the flow of air "fromsaid room into said air intake forming means, past said evaporator, andout of said air discharge forming means; control means including aswitch for causing operation of said air sirculator motor whenever saidcompressor motor operates, and a device responsive to a psychro- .metricfunction of air conditions in said room may be condensed from the airpassing over said evaporator; said condenser being water cooled;

air intake forming means in saida water circulating air coolingapparatus in said in the path of said flow of evaporator, and a sourceof supply of water for said water circulating, air cooling apparatus andsaid condenser.

20. A unitary room cooler and dehumidifier to be used in a room or thelike where refrigeration .is desired to maintain the temperature andhumidity of the air in said room or the like within the values boundingthe human comfort range, comprising a cabinet with upright substantiallyvertical walls with an upper air cooling and dehumidifying section and alower refrigerant circulating section; a refrigerant evaporator in saidupper section; a refrigerant compressor, an electric compressor motordrivingly connected to said compressor and a refrigerant condenser insaid lower section; said evaporator, compressor and condenser beingconnected in refrigerant flow relationship; air intake forming means insaid cabinet located a substantial distance above the floor of said roomto introduce air from said room into the lower part of said uppersection; air discharge forming means in the upper part of said uppersection; an air circulator and an electric air circulator motordrivingly connected to said air circulator causing the flow of air fromsaid room into said air intake forming means, past said evaporator, andout of said air discharge forming means; control means including aswitch for causing operation of said air circulator motor whenever saidcompressor motor operates, and a device responsive to a psychrometricfunction of air conditions in said room controlling the operation ofsaid compressor; said air circulator, evaporator, compressor andcondenser being correlated with each other to maintain said evaporatortemperature above freezing and below the minimum dew point temperatureprevailing at a time when artificial air cooling is desired, whereby theaccumulation of frost on said evaporator is prevented and moisture maybe condensed from the air passing over said evaporator; and an airreheating coil in said upper section located in the path of said flow ofair to reheat the air after it flows past said evaporator, said airreheating coil utilizing part of the heat of liquefaction of therefrigerant circulated by said compressor.

HARRY B. HULL.

